Automatic shut-off for pumps



' 1,639,147 1927' A. A. PHILLIPS ET AL AUTOMATIC SHUT-OFF FOR PUMPS Filed Nov. 8. 1926 Z'nvenlot Patented Aug. 16, 1927.

UNITED STATES PATENT OFFICE.

ARTHUR ALBERT PHILLIPS, OF ANAHEIM, AND EDWARD CONNELLY, OF FULLERTON,

CALIFORNIA.

AUTOMATIC SHUT-err FOR PUMPS.

Application filed November 8, 1926. Serial No. 146,874.

This invention relates to an automatic shut-off for pumps. The invention is particularly applicable to pumps, the plungers of which are not connected to a wheel or crank, for example, pumps of the duplex type. In using these pumps, it sometimes happens that the supply of the water, or other liquid being pumped, fails, and when this occurs, the pumps are apt to race.

In order to prevent injury to the pump, it is necessary to shut off the operating fluid or steam immediately. The general object of this invention is to provide a device for effecting this; also to provide a construct-ion for the device which will enable the steam to be substantially shut off but not complete- Other objects of the invention will appear hereinafter.

The invention consists in the novel parts and combinations of parts to be described hereinafter, all of which contribute to produce an efiioient automatic shut-off for pumps.

A preferred embodiment of the inventlon is described in the following specification, while the broad scope of the invention is pointed out in the appended claims.

In the drawings:

Figure 1 is an end elevation of a duplex pump having apparatus embodying our invention. v

Figure 2 is a vertical section through the end of the pump cylinder upon an enlarged scale and also illustrating a portion of the steam pipe for the pump, broken away, together with the device which we may employ for automatically shutting ofi the steam.

In applying our invention to a pump, we make use of the fact that when the supply of water or other liquid fails, the piston or plunger of the pump will immediately develop an over-stroke, that is, the stroke of the piston or plunger will be greater than the normal stroke. In order to utilize this over-stroke to effectthe closing olf of steam, we provide a connection through-thecylinder wall. Obviously, this connection can be placed either through the wall of a steam cylinder or a pump cylinder. We prefer, however, to provide the connection through one of the heads of a steam cylinder. 'I-Ience, carrying out the invention, we

provide a member which projects into the interior of the cylinder but which lies beyond the normal path of movement of the piston which is to operate it. When the pump is in normal operation, this member is not struck but when the pump begins to race, this member will be struck and moved outwardly. This outward movement of the member is utilized to actuate the controlling device for shutting off the flow of the operating fluid.

In the drawings, illustrating the preferred embodiment of the invention 1, 1 represent two cylinders of a duplex pump, which pump is supplied with operating fluid such as steam, through a steam connection 2 and manifold 3. The steam connection 2 includes a valve 4 which is preferably of the butterfly type or any other type which can be substantially closed by a relatively small amount, of movement. In a valve of this type, we provide the valve with a long stem or spindle 5 which is rotatably mounted in a bracket 6. This bracket has a foot 7 at one end which is clamped upon the boss 8 on the side of the pipe where the valve is located; and opposite this foot, the outer end of the spindle is rotatably mounted in the upper end of a vertical extension or arm 9 of the bracket 6. Cooperating with the valve, We provide a trip device which includes a member that engages with the spindle 5 to hold it in a position which will keep the valve 4 in its open position but which, when actuated by the over-stroke of the piston, will release the valve and permit it to close. In order to accomplish this, we provide the spindle 5 with a means for urging it toward its closed position. For this purpose,.we employ a coil spring 10 disposed around the spindle 5, one end of which is secured to the bracket 6 and the other end of which is secured to a collar 11 fixed on the spindle. In order to latch the valve 4 in its open position, we provide means such as a notch 12 in the projecting end of the spindle and this notch is engaged by a long arm of a trip lever 13, said lever having a short arm or toe 14 which is located near the end of a movable member or plunger 15 which is mounted to slide through the head 16 of the cylinder 1. In other words, the trip lever 13 has its pivot 17 on the vertical arm 9 of the bracket.

vThe plunger or actuating member 15 is in the form of a stem which is mounted to slide in a bushing 18 in the cylinder head 16 and has a hardened conical tip 19 which is in axial alinement with the end of the piston rod 20. If desired, this plunger may be held tightly in ordinary packing which is sufliciently tight to prevent the plunger from being forced outwardly by the pressure within the cylinder. e prefer, however, to provide the plunger or stem with a coil spring 21 which is disposed around it with one end thrusting against the bushing 18 and the other end against the outer face of the head 19. The bushing 18 may be provided with a suitable stutling 130x22 to prevent leakage. The outer end of the plunger 15 has an adjustable threaded extension 23.

I'Vhen the end of the trip lever 13 is in engagement with the notch 12, as shown in Figure 2, the valve l is held in its open position but is constrained or urged toward its closed position by the spring. hen an over-stroke of the piston occurs, the end of the piston rod 20 strikes the head 19 and forces the plunger or stem 15 outwardly. This will move the short arm or toe 14 of the trip lever toward the left and disengage the upper end of the trip lever from the spindle. This will permit the spring to close the valve.

In practice, however, we prefer to provide means for preventing the valve from closing completely and incidentally this means provides means for rotating the spindle to place it in its set position. For this purpose, we provide spindle 5 with a rigidly attached lever 24 and this lever swings in the direction of the arrow when the device operate In order to limit the closing movement of the valve, we provide a small adjustable setserew 25 in the path of this lever. This adjusting screw is mounted in the bracket 6 and can be adjusted up or down as desired so as to leave the valve as far open as desired when the apparatus operates as shut off.

e provide means for adjusting the position of the head 19. For this purpose, adjusting nuts 26 are provided on the threads of the stem 15, seating on the end of the bushing so as to limit the inward movement of the stem. They enable the stem to be adjusted in or out as may be desired.

In order to adjust the length of the stem 15 at its outer end, we provide it with adjusting nuts 27.

What we claim is: v

1. In an automatic shut-off for a pump having a cylinder and a reciprocating piston, the combination of a member projecting into the interior of the cylinder and lying beyond he normal path of movement of the piston when the pump is in normal operation, acontrolling device for controlling the flow of operating fluid to the pump to drive the piston, and means actuated by said member to actuate the controlling device to shut off flow of the operating fluid when said member is struck by the piston.

52-. In an automatic shut-off for a pump having a cylinder and a reciprocating pis- ."f

ton, the combination of a member extending through the cylinder head into the interior of the cylinder and lying beyond the normal )ath of movementof the piston, a valve for controlling the How of operating fluid to the pump to drive the piston, and means actuated by said member to actuate the valve and shut oif flow of the operating fluid when said member is struck by the piston.

3. In an automatic shut-01f for a pump having a cylinder and a reciprocating pis ton, the combination of a plunger guided to slide through the cylinder head substantially parallel to the direction ofmovement' of the piston, extending into the interior of the cyl inder and lying beyond the normal path of movement of the piston when the pump is in normal operation, a valve with means for closing the same to control the flow of operating fluid to the pump to drive the piston,

a trip-device associated with the valve and operating to hold the valve open, said tripdevice having a part in the path of move ment of said plunger and actuated by the plunger to trip the trip-device and eife'ct the closing of the valve when the piston stroke increases beyond the normal stroke.

4:. In an automatic shut ofl for a pump having a cylinder and a reciprocating piston, the combination of a plunger mounted to slide through the cylinder head, projecting into the interior of the cylinder and lying beyond the normal path of movement of the piston when the pump is in operation, a valve for controlling the flow of operating fluid to the pump to drive the piston, said valve having a spring for closing the same, latching means for latching the valve in the open position. said latching means having a part in the path of the plunger and operating to release the valve and permit the same to close when the piston stroke increases beyond the nominal stroke.

5. In an automatic shut-off for a pump having a cylinder and a reciprocating piston. the combination of a plunger guided to slide through the cylinder head, projecting into the interior of the cylinder and lying be yohd the normal path of movement of the piston whenthe pump is in normal opera-- tion. a valve for controlling the flow of operating fluid to the pump to drive the piston, said valve having a rotatable stem for closing the same, a spring mounted so as to urge the valve toward its 'closed posit ion, and a trigger cooperating with the stem to latch the valve in its open position, said trigger having a part projecting into the path of the plunger to release the stem and effect the closing of the valve when. the pislot] ton stroke increases beyond the normal stroke sufficiently to strike the plunger.

6. In an automatic shut-cit for a pump having a cylinder and a reciprocating piston, the combination of a member projecting into the interior of the cylinder and lying beyond the normal path of movement of the piston when the pump is in normal operation, a controlling device for controlling the flow of operating fluid to the pump to drive the piston, means actuated by said member to actuate the controlling device and sub stantially shut oii' flow of the operating fluid when the piston stroke increases sufliciently beyond the normal stroke, and means associated with the controlling device to prevent the same from completely shutting off the flow of the operating fluid.

7. In an automatic shut-off for a pump having a cylinder and a reciprocating piston, the combination of a plunger guided to slide through the cylinder head, projecting into the interior of the cylinder and lying beyond the normal path of movement of the piston when the pump is in normal operation, a valve for controlling the How of operating fluid to the pump to drive the piston, said valve having a rotatable stem for closing the same, a spring mounted so as to urge the valve toward its closed position, a trig er cooperating with the stem to latch the va ve in its open position, said trigger having a part projecting into the path of the plunger to release the stem and efl'ect the closing of the valve When the piston stroke increases 1 interior of the cylinder and lying beyond the normal path of movement of the piston when the pump is in normal operation, a valve having a rotary stem, for controlling the flow of operating fluid to the pump to drive the piston, a spring associated with the valve stem and mounted so as to urge the valve toward its closed position, a lever rigid with the valve stem, a trigger in the path of movement of the plunger so as to be actuated thereby if the plunger is struck by the piston, said stem having means cooperating with the trigger to latch the valve in its open position, and means in the path of the lever for limiting the closing movement of the valve.

Signed at Buena Park, California, this 6th day of October, 1926.

ARTHUR ALBERT PHILLIPS.

Signed at Buena Park, California, this 6th day of October, 1926.

EDW'ARD CONNELLY. 

